Scientists from the University of Texas at Austin have studied a strange depression on Mars that may be a good bet for finding life.
The depression caught the attention of the researchers because it appears to be similar to “ice cauldrons” on Earth. This is where a volcano has erupted through an ice sheet or glacier, creating a large funnel that narrows as you get deeper.
It's located within the largest impact crater we know of in the Solar System, called the Hellas basin, which is about 2,300 kilometers (1,400 miles) across. And it was of particular interest because of concentric rings seen around its exterior, evidence of volcanic activity.
If confirmed as being formed by a volcano, the depression would be of particular interest because it could be a chemical-rich environment well suited for life. A paper describing the latest findings was published in the journal Icarus.
"We were drawn to this site because it looked like it could host some of the key ingredients for habitability – water, heat and nutrients," lead author Joseph Levy from the University of Texas Institute for Geophysics said in a statement.
The Hellas depression was actually one of two studied by the researchers in images taken by the Mars Reconnaissance Orbiter (MRO). Another, in a region called Galaxias Fossae, has a similar appearance. Two theories had been touted for their formation, either this “ice cauldron” idea that melted away surface ice, or an asteroid impact.
Based on 3D models, the researchers now think the two formed in different ways. Galaxias Fossae was probably the result of an impact, based on debris spread around the region, whereas the Hellas depression lacks such debris – hinting at a volcanic origin.
Mars is thought to have been at its peak volcanic activity between 3.7 billion and 500 million years ago. We don’t have any evidence for volcanic eruptions today, although there are some hints it may still occur.
Nonetheless, if the Hellas depression really was formed by a volcano, it could be a good location to look for signs of life. A combination of liquid water and chemical nutrients could make it a prime target for future study.
Image in text: An ice cauldron in Iceland's Vatnajökull ice cap. Oddur Sigurðsson/Icelandic Meteorological Office